Welcome to brain Stuff production of iHeartRadio. Hey brain Stuff, Lauren Vogel bomb here. Why are millennia old ancient Roman piers still standing strong is veritable concrete islands, while modern concrete structures built only decades ago crumble from an onslaught of wind and waves. The answer lies in until now
undocumented Roman recipe. Researchers at the University of Utah have discovered that a seawater filters through piers and breakwaters made of age old Roman concrete, the structures actually become increasingly stronger because of the growth of interlocking minerals, including some minerals that are rare or expensive to cultivate in lab settings.
The study, published in the journal American Mineralogist, found that as seawater percolates through the concrete in the piers and breakwaters, it dissolves parts of the volcanic ash that was used in construction. This allows new minerals like aluminum, tobomerite, and philip site to form from the leached fluid. It's These minerals, similar in shape to the crystals and volcanic rocks, then form interlocking plates in gaps within the ancient concrete, making
the concrete stronger over time. This is pretty much the opposite of what happens to modern concrete structures, which are worn down by the elements and become increasingly cracked and brittle as pores and gaps are compromised by infiltrating sea water. So why aren't we using Roman style concrete? For one,
we don't know the recipe. We may think we're at the height of human knowledge, and certainly the Internet gives everyone who has access a leg up, but the ancients had techniques and technologies that have been lost to time. Although University of Utah geologist and lead study author Marie Jackson has poured through ancient Roman texts, she hasn't yet discovered a precise method for mixing the marine mortar, but she's working with geological engineers to recreate the right mix.
There's also a load bearing issue. Ancient is the key word in these Roman structures, which took a long long time to develop their strength from seawater. Young cement built using a Roman recipe probably wouldn't have the compressive strength to handle modern use, at least not initially, but that doesn't mean concocting a concrete mix using Roman engineering savvy
wouldn't be useful. The concrete could potentially be used to replace other corrodable building materials like steel and modern concrete in newly constructed tidal lagoons, for instance, and other see or see adjacent structures. Maybe in the future we can put this ancient knowledge to use. Today's episode was written by Laurie L. Dove and produced by Tyler Clang. Brain
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